1. Field of the Invention
The present invention relates to an ultrasonic surgical instrument which uses ultrasonic vibration to treat living tissue.
2. Description of the Related Art
For example, Jpn. Pat. Appln. KOKAI Publication No. 2009-82711 has disclosed a surgical treatment instrument which uses ultrasonic vibration to treat living tissue. That is, in this surgical treatment instrument, a proximal end portion of a probe is coupled to an ultrasonic vibrator. The probe is inserted through an insertion sheath, and a distal end portion of the probe protrudes from a distal end portion of the insertion sheath to form a treatment section. On the other hand, a grip member that can be opened or closed relative to the treatment section is disposed in the distal end portion of the insertion sheath. The grip member is closed relative to the treatment section so that the living tissue can be gripped by the treatment section and the grip member. While the living tissue is gripped by the treatment section and the grip member, ultrasonic vibration generated by the ultrasonic vibrator is transmitted by the probe to ultrasonically vibrate the treatment section. Consequently, it is possible to carry out a coagulation/cutting treatment.
Moreover, for example, Jpn. Pat. Appln. KOKAI Publication No. 2009-82710 has disclosed a surgical treatment instrument similar to the surgical treatment instrument disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2009-82711.
In the above-mentioned surgical treatment instrument, the grip member is opened or closed relative to the treatment section, whereby the living tissue is gripped by the grip member and the treatment section. A distal end portion side of the surface of the treatment section which faces at least the grip member is curved toward a central axis of a probe 29 for the enhancement of removing properties in the treatment section relative to the living tissue and for the decrease of cavitations in the treatment section. The distal end portion side is curved away from the grip member. Moreover, the grip member is linearly formed.